CHANNEL Corn Products Response to High pH Soils - 2021

Trial Objective

Corn products often respond differently to high pH soils. A high soil pH is generally classified as 7.6 or higher, and key nutrients, including iron, are tied up in these more alkaline soils. Products with a low tolerance to soils with a high pH can express iron deficiency chlorosis (IDC) resulting in symptoms such as yellow leaves, interveinal chlorosis, and stunted growth. Corn products vary in their tolerance to pH and can be considered susceptible, semi-tolerant, or tolerant to the effects of high soil pH. A better understanding of product performance under varying soil pH conditions is important for positioning products to help maximize yield potential. 

In Western Kansas and Eastern Colorado, high soil pH occurs due to the weathering of soil parent material that is high in calcium carbonate.  The objective of this ongoing trial is:

• To determine the visual and yield response of a range of different corn products to high pH (7.6-8.5) soils.  

Research Site Details

• For this trial, a total of 92 different commercial and experimental Channel® brand corn products of varying relative maturities (RMs) were each planted in one pH block at each location. 
  • 4 products had RMs ranging from 93-day to 97-day.  
  • 22 products had RMs ranging from 98-day to 103-day.
  • 29 products had RMs ranging from 104-day to 107-day.
  • 32 products had RMs ranging from 108- to 112-day.
  • 5 products had RMs ranging from 113-day to 114-day.
• Sixteen of the products tested in this study were Channel® RIB Complete® brand blend corn products; only the results of the Channel® products are shown in this report.
• A visual color rating of the foliage was taken at the V8 and VT growth stages: 
  • very dark green = 2 
  • pale-yellow color = 8
• The average yield of each individual product was compared to the average yield of all the products within the RM group. 
• Each product was replicated 8 times at each location.
• Soil pH was determined by grid sampling each trial area at a 1/10th acre density.

Understanding the Results

• The 105RM check, known to have poor performance on high pH soils, had the lowest yield compared to similar RM products at -38.9bu/acre (Table 1).
• Channel products 197-27STXRIB brand blend, 201-14VT2PRIB brand blend, 203-60TRERIB brand blend, 210-60TRERIB brand blend, and 211-30VT2PRIB brand blend yielded above the RM yield average (Table 1).  In most cases, these products are recommended for high pH soils.
• Channel products 197-21VT2PRIB brand blend, 205-63STXRIB brand blend, 209-06STXRIB brand blend, 209-15STXRIB brand blend, 212-04STXRIB brand blend, and 214-22STXRIB brand blend had yield disadvantages less than 10 bu/acre when compared to the RM yield average (Table 1).  These corn products are recommended for high pH soils. 
• Channel products 193-91STXRIB brand blend, 200-88STXRIB brand blend, 204-30STXRIB brand blend, and 205-70STXRIB brand blend had yield disadvantages greater than 10 bu/acre when compared to the RM yield average, and it is recommended to use these products with caution on high pH soils (Table 1).

Key Learnings

• High pH soils are typically found in areas with eroded topsoil and topography changes, and due to field variability, it can be difficult to compare yields between neutral and high pH areas of the field. Producers need to keep this in mind while making yield comparisons on their own farms
• The importance of selecting a product able to tolerate high pH soils varies based on the proportion of high pH soil acres in each field and the range in pH within each field.  
• The pH tolerance of any corn product is indicated by a visual color rating. However, color expression can also be influenced by other abiotic factors such as soil temperature, nutrient availability, and nutrient uptake. Producers should assess all potential problems when evaluating product performance under high pH soils and when selecting specific products for their fields.

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Channel® Corn Products for High pH Soils - 2020

• A high soil pH is generally classified as having a soil pH of 7.6 or higher and could have the characteristics of excess lime, high soluble salt concentration, and high nitrate-nitrogen concentration. 
• In Western Kansas and Eastern Colorado, excess lime from high calcium carbonate concentrations in the soil parent material is the source of the high pH, which is found on eroded sidehills and cut areas in fields. 
• Corn products can respond differently to high pH soils, from tolerant to non-tolerant. Products that are non-tolerant usually express iron deficiency chlorosis (IDC) with symptoms including yellow leaves, interveinal chlorosis, and stunted growth. 
• Key nutrients, including iron, are tied up in high pH soils and not available to the plant.     
• Better product characterization allows for better product placement to maximize yield potential.
• The objective of this study was to determine the visual response of corn products to soil pH and yield potential in moderate pH (6.6 to 7.5) and high pH (7.6+) soils.  
  

• For this trial, 68 commercial and experimental corn products of varying relative maturities (RMs) were planted in two separate blocks in the same field. One block had a soil type with a high pH (7.6-8.1) and the other block was planted in soil with a neutral pH (6.6-7.5). 
  • 35 products had RMs ranging from 103- to 107-day and were grouped as 105 RM.  
  • 33 products had RMs ranging from 108- to 113-day and were grouped as 110 RM.
• Seven of these products were Channel® brand blend corn products; only the results of the Channel products are shown in this report. 
• A visual color rating of the foliage was taken at the V8 and VT growth stage: 
  • very dark green = 2 
  • pale-yellow color = 8 
• For each pH block, the average yield of each product was compared to the average yield of all products within the RM group. 
• Each trial was replicated in a high pH zone and a moderate pH zone in the same field at each block location. 
• Soil pH was determined by grid sampling each trial area at a 1/10th acre density.
• The trial was planted on a site that was previously planted in corn and a soil-applied insecticide was included across the trial to help control western corn rootworm. 

• Visual differences were not detected in any of the products when planted in neutral pH soils (data not shown).
• Average yields in this trial were less than expected this year and may have been a result of excessive heat and drought conditions.
• On the neutral pH block, the average yield of the 110 RM group was 3.1 bu/acre greater compared to the average yield of the 105 RM group. In optimal growing conditions, longer RM products generally have greater yield potential.  
• 205-63VT2PRIB Brand Blend, 212-04STXRIB Brand Blend, and 212-60TRERIB Brand Blend had green, healthy plant color at the V8 and VT growth stages and yielded greater than similar RM products on high pH soils and is highly recommended for high pH soils.
• 204-25VT2PRIB, Brand Blend, and 204-74VT2PRIB Brand Blend had average visual appearance but yielded greater than similar RM products on high and neutral pH soils. These products are highly recommended for high pH soils.
• 205-70STXRIB Brand Blend and 207-42STXRIB Brand Blend had below average visual ratings and slightly below averaging yields to comparable RM corn products, these products are recommended for most situations on high pH soils.

• High pH soils are typically found in areas with eroded top soil and topography changes, which make it difficult to compare yields between neutral and high pH areas of the field. Producers need to keep this in mind while making yield comparisons on their own farm.
• The importance of selecting a product able to tolerate high pH soils varies based on soil pH level and the proportion of high pH soil acres in each field.  
• Corn product pH tolerance was indicated by a visual color rating, but color expression can also be influenced by other abiotic factors such as soil temperature, nutrient availability, and nutrient uptake. Producers should assess all potential problems when assessing product performance under high pH soils.

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